Hi all, My wife has a Mid 2011 Macbook Air that has become very slow. A few weeks ago, I wiped the drive, reinstalled Mavericks and used the migration tool to transfer her data back to the computer and the computer seems to still be fairly slow. Would it be safe to assume that by using the migration tool, I brought the problems back to OS X? I know there are many different opinions on OS X and "clean installs" and the Windows reformatting mentality. However do you think it would be worth the time to wipe the drive and truly start from a blank slate? Do I even consider upgrading her to El Capitan? Does anyone with a Mid 2011 have any comments on how El Capitan has been running on their machine?